<?php

    /**
     * PHPExcel_Shared_String
     * Copyright (c) 2006 - 2015 PHPExcel
     * This library is free software; you can redistribute it and/or
     * modify it under the terms of the GNU Lesser General Public
     * License as published by the Free Software Foundation; either
     * version 2.1 of the License, or (at your option) any later version.
     * This library is distributed in the hope that it will be useful,
     * but WITHOUT ANY WARRANTY; without even the implied warranty of
     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     * Lesser General Public License for more details.
     * You should have received a copy of the GNU Lesser General Public
     * License along with this library; if not, write to the Free Software
     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
     * @category   PHPExcel
     * @package    PHPExcel_Shared
     * @copyright  Copyright (c) 2006 - 2015 PHPExcel (http://www.codeplex.com/PHPExcel)
     * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
     * @version    ##VERSION##, ##DATE##
     */
    class PHPExcel_Shared_String {
        /**    Constants                */
        /**    Regular Expressions        */
        //    Fraction
        const STRING_REGEXP_FRACTION = '(-?)(\d+)\s+(\d+\/\d+)';
        /**
         * Control characters array
         * @var string[]
         */
        private static $controlCharacters = [];
        /**
         * SYLK Characters array
         * $var array
         */
        private static $SYLKCharacters = [];
        /**
         * Decimal separator
         * @var string
         */
        private static $decimalSeparator;
        /**
         * Thousands separator
         * @var string
         */
        private static $thousandsSeparator;
        /**
         * Currency code
         * @var string
         */
        private static $currencyCode;
        /**
         * Is mbstring extension avalable?
         * @var boolean
         */
        private static $isMbstringEnabled;
        /**
         * Is iconv extension avalable?
         * @var boolean
         */
        private static $isIconvEnabled;

        public static function buildCharacterSets() {
            if (empty(self::$controlCharacters)) {
                self::buildControlCharacters();
            }
            if (empty(self::$SYLKCharacters)) {
                self::buildSYLKCharacters();
            }
        }

        /**
         * Build control characters array
         */
        private static function buildControlCharacters() {
            for ($i = 0; $i <= 31; ++$i) {
                if ($i != 9 && $i != 10 && $i != 13) {
                    $find                           = '_x' . sprintf('%04s', strtoupper(dechex($i))) . '_';
                    $replace                        = chr($i);
                    self::$controlCharacters[$find] = $replace;
                }
            }
        }

        /**
         * Build SYLK characters array
         */
        private static function buildSYLKCharacters() {
            self::$SYLKCharacters = [
                "\x1B 0"  => chr(0),
                "\x1B 1"  => chr(1),
                "\x1B 2"  => chr(2),
                "\x1B 3"  => chr(3),
                "\x1B 4"  => chr(4),
                "\x1B 5"  => chr(5),
                "\x1B 6"  => chr(6),
                "\x1B 7"  => chr(7),
                "\x1B 8"  => chr(8),
                "\x1B 9"  => chr(9),
                "\x1B :"  => chr(10),
                "\x1B ;"  => chr(11),
                "\x1B <"  => chr(12),
                "\x1B :"  => chr(13),
                "\x1B >"  => chr(14),
                "\x1B ?"  => chr(15),
                "\x1B!0"  => chr(16),
                "\x1B!1"  => chr(17),
                "\x1B!2"  => chr(18),
                "\x1B!3"  => chr(19),
                "\x1B!4"  => chr(20),
                "\x1B!5"  => chr(21),
                "\x1B!6"  => chr(22),
                "\x1B!7"  => chr(23),
                "\x1B!8"  => chr(24),
                "\x1B!9"  => chr(25),
                "\x1B!:"  => chr(26),
                "\x1B!;"  => chr(27),
                "\x1B!<"  => chr(28),
                "\x1B!="  => chr(29),
                "\x1B!>"  => chr(30),
                "\x1B!?"  => chr(31),
                "\x1B'?"  => chr(127),
                "\x1B(0"  => '€',
                // 128 in CP1252
                "\x1B(2"  => '‚',
                // 130 in CP1252
                "\x1B(3"  => 'ƒ',
                // 131 in CP1252
                "\x1B(4"  => '„',
                // 132 in CP1252
                "\x1B(5"  => '…',
                // 133 in CP1252
                "\x1B(6"  => '†',
                // 134 in CP1252
                "\x1B(7"  => '‡',
                // 135 in CP1252
                "\x1B(8"  => 'ˆ',
                // 136 in CP1252
                "\x1B(9"  => '‰',
                // 137 in CP1252
                "\x1B(:"  => 'Š',
                // 138 in CP1252
                "\x1B(;"  => '‹',
                // 139 in CP1252
                "\x1BNj"  => 'Œ',
                // 140 in CP1252
                "\x1B(>"  => 'Ž',
                // 142 in CP1252
                "\x1B)1"  => '‘',
                // 145 in CP1252
                "\x1B)2"  => '’',
                // 146 in CP1252
                "\x1B)3"  => '“',
                // 147 in CP1252
                "\x1B)4"  => '”',
                // 148 in CP1252
                "\x1B)5"  => '•',
                // 149 in CP1252
                "\x1B)6"  => '–',
                // 150 in CP1252
                "\x1B)7"  => '—',
                // 151 in CP1252
                "\x1B)8"  => '˜',
                // 152 in CP1252
                "\x1B)9"  => '™',
                // 153 in CP1252
                "\x1B):"  => 'š',
                // 154 in CP1252
                "\x1B);"  => '›',
                // 155 in CP1252
                "\x1BNz"  => 'œ',
                // 156 in CP1252
                "\x1B)>"  => 'ž',
                // 158 in CP1252
                "\x1B)?"  => 'Ÿ',
                // 159 in CP1252
                "\x1B*0"  => ' ',
                // 160 in CP1252
                "\x1BN!"  => '¡',
                // 161 in CP1252
                "\x1BN\"" => '¢',
                // 162 in CP1252
                "\x1BN#"  => '£',
                // 163 in CP1252
                "\x1BN("  => '¤',
                // 164 in CP1252
                "\x1BN%"  => '¥',
                // 165 in CP1252
                "\x1B*6"  => '¦',
                // 166 in CP1252
                "\x1BN'"  => '§',
                // 167 in CP1252
                "\x1BNH " => '¨',
                // 168 in CP1252
                "\x1BNS"  => '©',
                // 169 in CP1252
                "\x1BNc"  => 'ª',
                // 170 in CP1252
                "\x1BN+"  => '«',
                // 171 in CP1252
                "\x1B*<"  => '¬',
                // 172 in CP1252
                "\x1B*="  => '­',
                // 173 in CP1252
                "\x1BNR"  => '®',
                // 174 in CP1252
                "\x1B*?"  => '¯',
                // 175 in CP1252
                "\x1BN0"  => '°',
                // 176 in CP1252
                "\x1BN1"  => '±',
                // 177 in CP1252
                "\x1BN2"  => '²',
                // 178 in CP1252
                "\x1BN3"  => '³',
                // 179 in CP1252
                "\x1BNB " => '´',
                // 180 in CP1252
                "\x1BN5"  => 'µ',
                // 181 in CP1252
                "\x1BN6"  => '¶',
                // 182 in CP1252
                "\x1BN7"  => '·',
                // 183 in CP1252
                "\x1B+8"  => '¸',
                // 184 in CP1252
                "\x1BNQ"  => '¹',
                // 185 in CP1252
                "\x1BNk"  => 'º',
                // 186 in CP1252
                "\x1BN;"  => '»',
                // 187 in CP1252
                "\x1BN<"  => '¼',
                // 188 in CP1252
                "\x1BN="  => '½',
                // 189 in CP1252
                "\x1BN>"  => '¾',
                // 190 in CP1252
                "\x1BN?"  => '¿',
                // 191 in CP1252
                "\x1BNAA" => 'À',
                // 192 in CP1252
                "\x1BNBA" => 'Á',
                // 193 in CP1252
                "\x1BNCA" => 'Â',
                // 194 in CP1252
                "\x1BNDA" => 'Ã',
                // 195 in CP1252
                "\x1BNHA" => 'Ä',
                // 196 in CP1252
                "\x1BNJA" => 'Å',
                // 197 in CP1252
                "\x1BNa"  => 'Æ',
                // 198 in CP1252
                "\x1BNKC" => 'Ç',
                // 199 in CP1252
                "\x1BNAE" => 'È',
                // 200 in CP1252
                "\x1BNBE" => 'É',
                // 201 in CP1252
                "\x1BNCE" => 'Ê',
                // 202 in CP1252
                "\x1BNHE" => 'Ë',
                // 203 in CP1252
                "\x1BNAI" => 'Ì',
                // 204 in CP1252
                "\x1BNBI" => 'Í',
                // 205 in CP1252
                "\x1BNCI" => 'Î',
                // 206 in CP1252
                "\x1BNHI" => 'Ï',
                // 207 in CP1252
                "\x1BNb"  => 'Ð',
                // 208 in CP1252
                "\x1BNDN" => 'Ñ',
                // 209 in CP1252
                "\x1BNAO" => 'Ò',
                // 210 in CP1252
                "\x1BNBO" => 'Ó',
                // 211 in CP1252
                "\x1BNCO" => 'Ô',
                // 212 in CP1252
                "\x1BNDO" => 'Õ',
                // 213 in CP1252
                "\x1BNHO" => 'Ö',
                // 214 in CP1252
                "\x1B-7"  => '×',
                // 215 in CP1252
                "\x1BNi"  => 'Ø',
                // 216 in CP1252
                "\x1BNAU" => 'Ù',
                // 217 in CP1252
                "\x1BNBU" => 'Ú',
                // 218 in CP1252
                "\x1BNCU" => 'Û',
                // 219 in CP1252
                "\x1BNHU" => 'Ü',
                // 220 in CP1252
                "\x1B-="  => 'Ý',
                // 221 in CP1252
                "\x1BNl"  => 'Þ',
                // 222 in CP1252
                "\x1BN{"  => 'ß',
                // 223 in CP1252
                "\x1BNAa" => 'à',
                // 224 in CP1252
                "\x1BNBa" => 'á',
                // 225 in CP1252
                "\x1BNCa" => 'â',
                // 226 in CP1252
                "\x1BNDa" => 'ã',
                // 227 in CP1252
                "\x1BNHa" => 'ä',
                // 228 in CP1252
                "\x1BNJa" => 'å',
                // 229 in CP1252
                "\x1BNq"  => 'æ',
                // 230 in CP1252
                "\x1BNKc" => 'ç',
                // 231 in CP1252
                "\x1BNAe" => 'è',
                // 232 in CP1252
                "\x1BNBe" => 'é',
                // 233 in CP1252
                "\x1BNCe" => 'ê',
                // 234 in CP1252
                "\x1BNHe" => 'ë',
                // 235 in CP1252
                "\x1BNAi" => 'ì',
                // 236 in CP1252
                "\x1BNBi" => 'í',
                // 237 in CP1252
                "\x1BNCi" => 'î',
                // 238 in CP1252
                "\x1BNHi" => 'ï',
                // 239 in CP1252
                "\x1BNs"  => 'ð',
                // 240 in CP1252
                "\x1BNDn" => 'ñ',
                // 241 in CP1252
                "\x1BNAo" => 'ò',
                // 242 in CP1252
                "\x1BNBo" => 'ó',
                // 243 in CP1252
                "\x1BNCo" => 'ô',
                // 244 in CP1252
                "\x1BNDo" => 'õ',
                // 245 in CP1252
                "\x1BNHo" => 'ö',
                // 246 in CP1252
                "\x1B/7"  => '÷',
                // 247 in CP1252
                "\x1BNy"  => 'ø',
                // 248 in CP1252
                "\x1BNAu" => 'ù',
                // 249 in CP1252
                "\x1BNBu" => 'ú',
                // 250 in CP1252
                "\x1BNCu" => 'û',
                // 251 in CP1252
                "\x1BNHu" => 'ü',
                // 252 in CP1252
                "\x1B/="  => 'ý',
                // 253 in CP1252
                "\x1BN|"  => 'þ',
                // 254 in CP1252
                "\x1BNHy" => 'ÿ',
                // 255 in CP1252
            ];
        }

        /**
         * Convert from OpenXML escaped control character to PHP control character
         * Excel 2007 team:
         * ----------------
         * That's correct, control characters are stored directly in the shared-strings table.
         * We do encode characters that cannot be represented in XML using the following escape sequence:
         * _xHHHH_ where H represents a hexadecimal character in the character's value...
         * So you could end up with something like _x0008_ in a string (either in a cell value (<v>)
         * element or in the shared string <t> element.
         * @param     string $value Value to unescape
         * @return     string
         */
        public static function ControlCharacterOOXML2PHP($value = '') {
            return str_replace(array_keys(self::$controlCharacters), array_values(self::$controlCharacters), $value);
        }

        /**
         * Convert from PHP control character to OpenXML escaped control character
         * Excel 2007 team:
         * ----------------
         * That's correct, control characters are stored directly in the shared-strings table.
         * We do encode characters that cannot be represented in XML using the following escape sequence:
         * _xHHHH_ where H represents a hexadecimal character in the character's value...
         * So you could end up with something like _x0008_ in a string (either in a cell value (<v>)
         * element or in the shared string <t> element.
         * @param     string $value Value to escape
         * @return     string
         */
        public static function ControlCharacterPHP2OOXML($value = '') {
            return str_replace(array_values(self::$controlCharacters), array_keys(self::$controlCharacters), $value);
        }

        /**
         * Try to sanitize UTF8, stripping invalid byte sequences. Not perfect. Does not surrogate characters.
         * @param string $value
         * @return string
         */
        public static function SanitizeUTF8($value) {
            if (self::getIsIconvEnabled()) {
                $value = @iconv('UTF-8', 'UTF-8', $value);
                return $value;
            }
            if (self::getIsMbstringEnabled()) {
                $value = mb_convert_encoding($value, 'UTF-8', 'UTF-8');
                return $value;
            }
            // else, no conversion
            return $value;
        }

        /**
         * Get whether iconv extension is available
         * @return boolean
         */
        public static function getIsIconvEnabled() {
            if (isset(self::$isIconvEnabled)) {
                return self::$isIconvEnabled;
            }
            // Fail if iconv doesn't exist
            if (!function_exists('iconv')) {
                self::$isIconvEnabled = false;
                return false;
            }
            // Sometimes iconv is not working, and e.g. iconv('UTF-8', 'UTF-16LE', 'x') just returns false,
            if (!@iconv('UTF-8', 'UTF-16LE', 'x')) {
                self::$isIconvEnabled = false;
                return false;
            }
            // Sometimes iconv_substr('A', 0, 1, 'UTF-8') just returns false in PHP 5.2.0
            // we cannot use iconv in that case either (http://bugs.php.net/bug.php?id=37773)
            if (!@iconv_substr('A', 0, 1, 'UTF-8')) {
                self::$isIconvEnabled = false;
                return false;
            }
            // CUSTOM: IBM AIX iconv() does not work
            if (defined('PHP_OS') && @stristr(PHP_OS, 'AIX') && defined('ICONV_IMPL') && (@strcasecmp(ICONV_IMPL, 'unknown') == 0) && defined('ICONV_VERSION') && (@strcasecmp(ICONV_VERSION, 'unknown') == 0)) {
                self::$isIconvEnabled = false;
                return false;
            }
            // If we reach here no problems were detected with iconv
            self::$isIconvEnabled = true;
            return true;
        }

        /**
         * Get whether mbstring extension is available
         * @return boolean
         */
        public static function getIsMbstringEnabled() {
            if (isset(self::$isMbstringEnabled)) {
                return self::$isMbstringEnabled;
            }
            self::$isMbstringEnabled = function_exists('mb_convert_encoding') ? true : false;
            return self::$isMbstringEnabled;
        }

        /**
         * Check if a string contains UTF8 data
         * @param string $value
         * @return boolean
         */
        public static function IsUTF8($value = '') {
            return $value === '' || preg_match('/^./su', $value) === 1;
        }

        /**
         * Formats a numeric value as a string for output in various output writers forcing
         * point as decimal separator in case locale is other than English.
         * @param mixed $value
         * @return string
         */
        public static function FormatNumber($value) {
            if (is_float($value)) {
                return str_replace(',', '.', $value);
            }
            return (string)$value;
        }

        /**
         * Converts a UTF-8 string into BIFF8 Unicode string data (8-bit string length)
         * Writes the string using uncompressed notation, no rich text, no Asian phonetics
         * If mbstring extension is not available, ASCII is assumed, and compressed notation is used
         * although this will give wrong results for non-ASCII strings
         * see OpenOffice.org's Documentation of the Microsoft Excel File Format, sect. 2.5.3
         * @param string  $value    UTF-8 encoded string
         * @param mixed[] $arrcRuns Details of rich text runs in $value
         * @return string
         */
        public static function UTF8toBIFF8UnicodeShort($value, $arrcRuns = []) {
            // character count
            $ln = self::CountCharacters($value, 'UTF-8');
            // option flags
            if (empty($arrcRuns)) {
                $opt  = (self::getIsIconvEnabled() || self::getIsMbstringEnabled()) ? 0x0001 : 0x0000;
                $data = pack('CC', $ln, $opt);
                // characters
                $data .= self::ConvertEncoding($value, 'UTF-16LE', 'UTF-8');
            } else {
                $data = pack('vC', $ln, 0x09);
                $data .= pack('v', count($arrcRuns));
                // characters
                $data .= self::ConvertEncoding($value, 'UTF-16LE', 'UTF-8');
                foreach ($arrcRuns as $cRun) {
                    $data .= pack('v', $cRun['strlen']);
                    $data .= pack('v', $cRun['fontidx']);
                }
            }
            return $data;
        }

        /**
         * Get character count. First try mbstring, then iconv, finally strlen
         * @param string $value
         * @param string $enc Encoding
         * @return int Character count
         */
        public static function CountCharacters($value, $enc = 'UTF-8') {
            if (self::getIsMbstringEnabled()) {
                return mb_strlen($value, $enc);
            }
            if (self::getIsIconvEnabled()) {
                return iconv_strlen($value, $enc);
            }
            // else strlen
            return strlen($value);
        }

        /**
         * Convert string from one encoding to another. First try mbstring, then iconv, finally strlen
         * @param string $value
         * @param string $to   Encoding to convert to, e.g. 'UTF-8'
         * @param string $from Encoding to convert from, e.g. 'UTF-16LE'
         * @return string
         */
        public static function ConvertEncoding($value, $to, $from) {
            if (self::getIsIconvEnabled()) {
                return iconv($from, $to, $value);
            }
            if (self::getIsMbstringEnabled()) {
                return mb_convert_encoding($value, $to, $from);
            }
            if ($from == 'UTF-16LE') {
                return self::utf16_decode($value, false);
            } elseif ($from == 'UTF-16BE') {
                return self::utf16_decode($value);
            }
            // else, no conversion
            return $value;
        }

        /**
         * Decode UTF-16 encoded strings.
         * Can handle both BOM'ed data and un-BOM'ed data.
         * Assumes Big-Endian byte order if no BOM is available.
         * This function was taken from http://php.net/manual/en/function.utf8-decode.php
         * and $bom_be parameter added.
         * @param   string $str UTF-16 encoded data to decode.
         * @return  string  UTF-8 / ISO encoded data.
         * @access  public
         * @version 0.2 / 2010-05-13
         * @author  Rasmus Andersson {@link http://rasmusandersson.se/}
         * @author  vadik56
         */
        public static function utf16_decode($str, $bom_be = true) {
            if (strlen($str) < 2) {
                return $str;
            }
            $c0 = ord($str{0});
            $c1 = ord($str{1});
            if ($c0 == 0xfe && $c1 == 0xff) {
                $str = substr($str, 2);
            } elseif ($c0 == 0xff && $c1 == 0xfe) {
                $str    = substr($str, 2);
                $bom_be = false;
            }
            $len    = strlen($str);
            $newstr = '';
            for ($i = 0; $i < $len; $i += 2) {
                if ($bom_be) {
                    $val = ord($str{$i}) << 4;
                    $val += ord($str{$i + 1});
                } else {
                    $val = ord($str{$i + 1}) << 4;
                    $val += ord($str{$i});
                }
                $newstr .= ($val == 0x228) ? "\n" : chr($val);
            }
            return $newstr;
        }

        /**
         * Converts a UTF-8 string into BIFF8 Unicode string data (16-bit string length)
         * Writes the string using uncompressed notation, no rich text, no Asian phonetics
         * If mbstring extension is not available, ASCII is assumed, and compressed notation is used
         * although this will give wrong results for non-ASCII strings
         * see OpenOffice.org's Documentation of the Microsoft Excel File Format, sect. 2.5.3
         * @param string $value UTF-8 encoded string
         * @return string
         */
        public static function UTF8toBIFF8UnicodeLong($value) {
            // character count
            $ln = self::CountCharacters($value, 'UTF-8');
            // option flags
            $opt = (self::getIsIconvEnabled() || self::getIsMbstringEnabled()) ? 0x0001 : 0x0000;
            // characters
            $chars = self::ConvertEncoding($value, 'UTF-16LE', 'UTF-8');
            $data = pack('vC', $ln, $opt) . $chars;
            return $data;
        }

        /**
         * Get a substring of a UTF-8 encoded string. First try mbstring, then iconv, finally strlen
         * @param string $pValue  UTF-8 encoded string
         * @param int    $pStart  Start offset
         * @param int    $pLength Maximum number of characters in substring
         * @return string
         */
        public static function Substring($pValue = '', $pStart = 0, $pLength = 0) {
            if (self::getIsMbstringEnabled()) {
                return mb_substr($pValue, $pStart, $pLength, 'UTF-8');
            }
            if (self::getIsIconvEnabled()) {
                return iconv_substr($pValue, $pStart, $pLength, 'UTF-8');
            }
            // else substr
            return substr($pValue, $pStart, $pLength);
        }

        /**
         * Convert a UTF-8 encoded string to upper case
         * @param string $pValue UTF-8 encoded string
         * @return string
         */
        public static function StrToUpper($pValue = '') {
            if (function_exists('mb_convert_case')) {
                return mb_convert_case($pValue, MB_CASE_UPPER, "UTF-8");
            }
            return strtoupper($pValue);
        }

        /**
         * Convert a UTF-8 encoded string to lower case
         * @param string $pValue UTF-8 encoded string
         * @return string
         */
        public static function StrToLower($pValue = '') {
            if (function_exists('mb_convert_case')) {
                return mb_convert_case($pValue, MB_CASE_LOWER, "UTF-8");
            }
            return strtolower($pValue);
        }

        /**
         * Convert a UTF-8 encoded string to title/proper case
         *    (uppercase every first character in each word, lower case all other characters)
         * @param string $pValue UTF-8 encoded string
         * @return string
         */
        public static function StrToTitle($pValue = '') {
            if (function_exists('mb_convert_case')) {
                return mb_convert_case($pValue, MB_CASE_TITLE, "UTF-8");
            }
            return ucwords($pValue);
        }

        /**
         * Reverse the case of a string, so that all uppercase characters become lowercase
         *    and all lowercase characters become uppercase
         * @param string $pValue UTF-8 encoded string
         * @return string
         */
        public static function StrCaseReverse($pValue = '') {
            if (self::getIsMbstringEnabled()) {
                $characters = self::mb_str_split($pValue);
                foreach ($characters as &$character) {
                    if (self::mb_is_upper($character)) {
                        $character = mb_strtolower($character, 'UTF-8');
                    } else {
                        $character = mb_strtoupper($character, 'UTF-8');
                    }
                }
                return implode('', $characters);
            }
            return strtolower($pValue) ^ strtoupper($pValue) ^ $pValue;
        }

        public static function mb_str_split($string) {
            # Split at all position not after the start: ^
            # and not before the end: $
            return preg_split('/(?<!^)(?!$)/u', $string);
        }

        public static function mb_is_upper($char) {
            return mb_strtolower($char, "UTF-8") != $char;
        }

        /**
         * Identify whether a string contains a fractional numeric value,
         *    and convert it to a numeric if it is
         * @param string &$operand string value to test
         * @return boolean
         */
        public static function convertToNumberIfFraction(&$operand) {
            if (preg_match('/^' . self::STRING_REGEXP_FRACTION . '$/i', $operand, $match)) {
                $sign            = ($match[1] == '-') ? '-' : '+';
                $fractionFormula = '=' . $sign . $match[2] . $sign . $match[3];
                $operand         = PHPExcel_Calculation::getInstance()->_calculateFormulaValue($fractionFormula);
                return true;
            }
            return false;
        }    //    function convertToNumberIfFraction()

        /**
         * Get the decimal separator. If it has not yet been set explicitly, try to obtain number
         * formatting information from locale.
         * @return string
         */
        public static function getDecimalSeparator() {
            if (!isset(self::$decimalSeparator)) {
                $localeconv             = localeconv();
                self::$decimalSeparator = ($localeconv['decimal_point'] != '') ? $localeconv['decimal_point'] : $localeconv['mon_decimal_point'];
                if (self::$decimalSeparator == '') {
                    // Default to .
                    self::$decimalSeparator = '.';
                }
            }
            return self::$decimalSeparator;
        }

        /**
         * Set the decimal separator. Only used by PHPExcel_Style_NumberFormat::toFormattedString()
         * to format output by PHPExcel_Writer_HTML and PHPExcel_Writer_PDF
         * @param string $pValue Character for decimal separator
         */
        public static function setDecimalSeparator($pValue = '.') {
            self::$decimalSeparator = $pValue;
        }

        /**
         * Get the thousands separator. If it has not yet been set explicitly, try to obtain number
         * formatting information from locale.
         * @return string
         */
        public static function getThousandsSeparator() {
            if (!isset(self::$thousandsSeparator)) {
                $localeconv               = localeconv();
                self::$thousandsSeparator = ($localeconv['thousands_sep'] != '') ? $localeconv['thousands_sep'] : $localeconv['mon_thousands_sep'];
                if (self::$thousandsSeparator == '') {
                    // Default to .
                    self::$thousandsSeparator = ',';
                }
            }
            return self::$thousandsSeparator;
        }

        /**
         * Set the thousands separator. Only used by PHPExcel_Style_NumberFormat::toFormattedString()
         * to format output by PHPExcel_Writer_HTML and PHPExcel_Writer_PDF
         * @param string $pValue Character for thousands separator
         */
        public static function setThousandsSeparator($pValue = ',') {
            self::$thousandsSeparator = $pValue;
        }

        /**
         *    Get the currency code. If it has not yet been set explicitly, try to obtain the
         *        symbol information from locale.
         * @return string
         */
        public static function getCurrencyCode() {
            if (!isset(self::$currencyCode)) {
                $localeconv         = localeconv();
                self::$currencyCode = ($localeconv['currency_symbol'] != '') ? $localeconv['currency_symbol'] : $localeconv['int_curr_symbol'];
                if (self::$currencyCode == '') {
                    // Default to $
                    self::$currencyCode = '$';
                }
            }
            return self::$currencyCode;
        }

        /**
         * Set the currency code. Only used by PHPExcel_Style_NumberFormat::toFormattedString()
         *        to format output by PHPExcel_Writer_HTML and PHPExcel_Writer_PDF
         * @param string $pValue Character for currency code
         */
        public static function setCurrencyCode($pValue = '$') {
            self::$currencyCode = $pValue;
        }

        /**
         * Convert SYLK encoded string to UTF-8
         * @param string $pValue
         * @return string UTF-8 encoded string
         */
        public static function SYLKtoUTF8($pValue = '') {
            // If there is no escape character in the string there is nothing to do
            if (strpos($pValue, '') === false) {
                return $pValue;
            }
            foreach (self::$SYLKCharacters as $k => $v) {
                $pValue = str_replace($k, $v, $pValue);
            }
            return $pValue;
        }

        /**
         * Retrieve any leading numeric part of a string, or return the full string if no leading numeric
         *    (handles basic integer or float, but not exponent or non decimal)
         * @param    string $value
         * @return    mixed    string or only the leading numeric part of the string
         */
        public static function testStringAsNumeric($value) {
            if (is_numeric($value)) {
                return $value;
            }
            $v = floatval($value);
            return (is_numeric(substr($value, 0, strlen($v)))) ? $v : $value;
        }
    }
